The present invention relates to systems for use with multiple safety devices such as self-retractable lifeline systems or self-retracting lanyard systems and connectors for use therewith, and, particularly, to systems enabling attachment of multiple self-retracting lifelines and to connectors for attaching multiple elements to a person wearing a safety harness.
The following information is provided to assist the reader to understand the invention disclosed below and the environment in which it will typically be used. The terms used herein are not intended to be limited to any particular narrow interpretation unless clearly stated otherwise in this document. References set forth herein may facilitate understanding of the present invention or the background of the present invention. The disclosures of all references cited herein are incorporated by reference.
In certain situations wherein a person wearing a safety harness is moving through a work area in which there is a potential for falling, it can be desirable for the person to attach a first lanyard or lifeline to a first solid anchor point and then move to a second anchor point and attach a second lanyard or lifeline to the second anchor point. After attaching the second lifeline to the second anchor point, the person can return to the first anchor point and disconnect the first lifeline. The person can then move forward past the second anchor point to a third anchor point and attach the first lifeline to the third anchor point and so on. By repeating this sequence, the person can move through a work area while always being connected by at least one lifeline to a solid anchor point. The first lifeline can, for example, be a harness-mounted self retracting lifeline (SRL) and the second lifeline can, for example, be a second harness-mounted self-retracting lifeline. Such devices are know alternatively as self-retracting lifelines, self-retracting lanyards, fall arrest blocks, etc. and have been developed to limit a worker's free fall distance to a specified distance and limit fall arresting forces to a specified value. A self-retracting lifeline is, for example, disclosed in U.S. Pat. No. 5,771,993, the disclosure of which is incorporated herein by reference. Self-retracting lifelines are, for example, available from Sperian Fall Protection, Inc. of Franklin, Pa. under the product trademarks SCORPION® Personal Fall Limiters, BLACK RHINO® Self-Retracting Lifelines, MINI-LITE® Fall Limiters, FALCON® Self-Retracting Lifelines, and MIGHTYLITE® Self-Retracting Lifelines.
In general, most currently available self retracting lifeline safety devices or systems include a number of common components. Typically, a housing or cover provides enclosure/protection for the internally housed components. The housing includes attached thereto a connector for anchoring the self-retracting lifeline to either the user or to a fixed anchor point. The connector must be capable of withstanding forces required to stop a falling body of a given mass in a given distance.
A drum or spool around which a lifeline is coiled or spooled rotates within the housing. The drum is typically under adequate rotational tension to reel up excess extended lifeline without hindering the mobility of the user. Like the anchor connector and the other operative components of the retractable lifeline safety device, the drum is typically formed to withstand forces necessary to stop a falling body of a given mass in a given distance. The lanyard or lifeline is attached at one end thereof to the drum to allow the drum to reel in excess lifeline. The lifeline is attached at the other end thereof to either the user or to an anchorage point, whichever is not already attached to the housing.
Self-retracting lifeline systems also include a mechanism which locks (that is, prevents rotation of) the drum assembly of the self-retracting lifeline upon indication that a fall is occurring. For example, when the rope, cable or web being pulled from the self-retracting lifeline system causes the drum assembly to rotate above a certain angular velocity or experience an angular acceleration above a certain level, a brake mechanism can cause the drum assembly to suddenly lock.
At least one currently available, harness-mounted device includes two independently operating lifeline retraction mechanisms built into a single frame and housing. However, there are a number of disadvantages associated with such a device. For example, when a user is moving horizontally, the webbing of the lifelines makes a 90 degree bend when entering or exiting the device, making extension of the lifeline difficult. There is, for example, often an inability to align with both anchor points during a transition form one anchor point to another. Bends in one of the lifelines can also prevent automatic retraction of the lifeline, allowing extra slack in the lifeline, and potentially increasing the free fall distance of the user. Additionally, if either retraction mechanism of the device becomes inoperative, the entire unit must be discarded or returned to the manufacturer for repair. Furthermore, manufacture of such a device requires the production of specialized sets of left and right hand parts which are unique to the device, while performing the complex functions of a self retracting lifeline or SRL.
Moreover, for a variety of situations including fall protection, travel restraint and rescue, there is a desire to have the ability to connect multiple safety devices to a single worker on a single connection to a harness. An example is the need to attach both a shock absorbing lanyard and self retracting lifeline to the same back D-Ring. Current embodiments of devices that allow connection of two devices require the use of an extension (for example, a length of webbing material) that creates a greater distance between the attached device(s) and the safety harness. This additional distance results in an increase in fall clearance as well as the ability for the devices to become twisted or intertwined or otherwise interfere with each other. There is also a restriction of the ability of each device to work and orient independently of each other.
It is desirable to develop improved devices, systems and methods that enable attachment of multiple self-retracting lifelines and other devices (particularly fall protection and rescue devices) to a person that reduce or eliminate the above-identified and/or other problems associated with current devices, systems and methods.